The research plan is to define and develop the coordination chemistry of iron-phenolate complexes as a basis for understanding the biochemistry of proteins containing iron-tyrosine coordination and other iron-phenolate interactions of biological significance. The extent and importance of the metal [particularly iron(III)] phenolate coordination in metalloproteins has only become evident in the last few years. The metal-tyrosine proteins, a newly recognized and rapidly growing class of metalloproteins, includes the transferrins, catechol dioxygenases, catalase, uteroferrin, and the iron and manganeses purple acid phosphatases. The investigation will basically involve the synthesis, structural characterization and spectroscopic study of a variety of iron(III)-phenolate complexes to serve as synthetic analogs for the metal coordination sites of these proteins. Particular emphasis will be given to the coordination chemistry of monodentate phenolates as models for the iron-tyrosine coordination mode. The inorganic chemistry of monodentate phenolates is virtually nonexistent due to neglect and lack of synthetic sophistication. The ultimate goal of this work is the synthesis and characterization of complexes which will duplicate the structural, eletronic and reactivity properties of the iron site in the iron-tyrosine proteins. In the effort to achieve that goal, new basic information will be provided about the biochemistry and chemistry of iron-phenolate interactions.